3D Textured Mesh

This is a 3D representation of the shape of a model that consists of vertices, edges, faces and the texture from the orthorectified images

Absolute Accuracy

Absolute accuracy refers to the difference between the location of the objects on the reconstructed model and their true position on the Earth

Digital Elevation Model (DEM)

Digital Elevation Model (DEM) is used here a as the generic term for DSMs and DTMs, only representing height information without any further definition about the surface.

Digital Surface Model (DSM)

A Digital Surface Model (DSM) represents the earth´s surface and includes all objects on it including natural objects such as trees and man-made objects such as buildings. A DSM is a 2.5 D model of the mapped area that contains (X,Y,Z) information, but no colour information

Digital Terrain Model (DTM)

Digital Terrain Model (DTM) represents the bare ground surface without any objects like trees and buildings. A DTM is a 2.5 D model of the mapped area that contains (X,Y,Z) information, but no colour information

Drone Operator

This is the person or organisation who manages the drone but it isn’t necessarily the person who is flying the drone. Think of this as the airline operator

Ground Control Points

Ground control points (GCPs) are large marked targets on the ground, spaced strategically throughout the area the drone is surveying. The ground control points and their RTK GPS coordinates are then used to help mapping and image processing software accurately position the images the drone has recorded in relation to the real world around it. Using GCPs can provide accuracy to within 3cm


An orthomosaic is a 2D map that is a detailed, accurate photo representation of an area, created out of many images that have been stitched together and geometrically corrected (“orthorectified”) so that it is as accurate as a map.


Unlike an uncorrected aerial photograph, an orthophotograph can be used to measure true distances, because it is an accurate representation of the Earth’s surface, having been orthorectified


The process of geometrically correcting images to correct for topographic relief, lens distortion, and camera tilt.